158955721 has 2 divisors, whose sum is σ = 158955722. Its totient is φ = 158955720.

The previous prime is 158955683. The next prime is 158955751. The reversal of 158955721 is 127559851.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 158886025 + 69696 = 12605^2 + 264^2 .

It is an emirp because it is prime and its reverse (127559851) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 158955721 - 2¹⁹ = 158431433 is a prime.

It is not a weakly prime, because it can be changed into another prime (158955751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79477860 + 79477861.

It is an arithmetic number, because the mean of its divisors is an integer number (79477861).

Almost surely, 2^158955721 is an apocalyptic number.

It is an amenable number.

158955721 is a deficient number, since it is larger than the sum of its proper divisors (1).

158955721 is an equidigital number, since it uses as much as digits as its factorization.

158955721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 126000, while the sum is 43.

The square root of 158955721 is about 12607.7643141042. The cubic root of 158955721 is about 541.6998571957.

The spelling of 158955721 in words is "one hundred fifty-eight million, nine hundred fifty-five thousand, seven hundred twenty-one".